cerebral crus
Enable an agent to identify a cerebral crus, assess evidence about its descending fibers and tissue state, and determine which observations or specialist review are warranted.
Bundle → Layer → Finding → Questions Filled
5 bundles · 9 layers · 14 findings · 22 questions
Crus identity and boundaries Establish which anatomical region a cerebral crus label denotes.
Terminology and reference
Anchor the registry concept to a declared anatomical convention.
Crus term resolution
Record the source label, its definition and whether it identifies the crus alone or a broader peduncular region.
- Does the source use cerebral crus or crus cerebri for the anterior tract-bearing region? definition
- Which terminology edition or atlas establishes what cerebral peduncle and basis pedunculi include here? provenance
Side and spatial limits
Define the individual crus and its limits within the examined midbrain.
Landmark-bounded region
Identify laterality, the substantia nigra interface and the rostral and caudal limits used for annotation.
- Which side and rostrocaudal extent does this annotation represent? boundary
- Which visible landmarks separate the crus from substantia nigra and adjoining fiber regions? boundary
Descending fiber organization Represent evidence about the cortical projection fibers traversing the crus.
Pathway membership
Connect local fibers to named descending pathways without modeling their entire courses.
Supported fiber identities
Record proposed corticospinal, corticonuclear and corticopontine assignments alongside the evidence supporting each.
- Which descending fiber populations are supported in this crus region, and by what anatomical or imaging evidence? provenance
- Where does the modeled local segment end and the linked whole-pathway model take over? boundary
Local topography
Qualify claims about fiber positions within a particular section of the crus.
Tract position confidence
Treat atlas sectors and tractography assignments as evidence-dependent estimates rather than fixed boundaries visible in every specimen.
- At this rostrocaudal level, what evidence supports the proposed relative positions of the fiber groups? provenance
- How much spatial uncertainty or overlap accompanies each local tract assignment? measurement
Crus observation and comparison Make measurements and comparisons interpretable for this small midbrain region.
Boundary visibility
Assess whether the observation method resolves the intended crus region.
Segmentation support
Record modality, resolution, orientation and the evidence used to draw the crus boundary.
- Which image contrast, stain or dissection feature supports the crus-substantia nigra boundary? provenance
- What resolution, partial-volume effect or deformation limits confidence in the segmented crus? measurement
Matched morphometry
Compare the two crura or repeated observations using equivalent anatomical extents.
Interpretable size comparison
Attach size differences to matched landmarks, methods and specimen context before interpreting them.
- What are the crus area or volume and uncertainty under the stated segmentation protocol? measurement
- Are side-to-side or longitudinal measurements matched for anatomical level, orientation and processing? measurement
Crus involvement and response Connect observed abnormalities to the crus while constraining functional and action claims.
Abnormality localization
Separate direct crus involvement, displacement and neighboring abnormalities.
Crus tissue involvement
Record the side, extent, timing and observed appearance of an abnormality without substituting a disease label for localization.
- Does the abnormality overlap crus tissue, displace it, or remain confined to adjacent structures? boundary
- What measured extent and temporal evidence support the recorded crus tissue state? measurement
Functional interpretation and review
Determine which pathway implications and follow-up actions the available evidence supports.
Bounded pathway interpretation
Link possible descending-pathway involvement to independent examination and pathway evidence, retaining alternative localization explanations.
- What independent evidence supports attributing the observed functional deficit to fibers affected within this crus? provenance
- Would further imaging, comparison with prior studies or specialist review resolve the uncertainty affecting interpretation? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these check these first hold for the sense of cerebral crus this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these identifiers and schemes hold for the sense of cerebral crus this model covers, and on what evidence? provenance
Standards and regulation
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these standards and regulation hold for the sense of cerebral crus this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these real-world use hold for the sense of cerebral crus this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these failure modes and hazards hold for the sense of cerebral crus this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of cerebral crus this model covers, and on what evidence? provenance
Classifiers Filled
- Family
- Thing Registry
- Category
- Physical world and living systems
- Entry kind
- thing
- Plane
- PHY
- Domain
- PHY.LIV
- Other names and narrower kinds
- Right cerebral crus, Left cerebral crus
What it is Filled
The cerebral crus (crus cerebri) is the paired ventral white-matter portion of the midbrain, lying anterior to the substantia nigra and carrying descending corticospinal, corticobulbar and corticopontine fibres.
In scope
- Identification of an individual left or right cerebral crus and its relationship to the paired crura
- Boundaries within the ventral midbrain and separation from adjacent substantia nigra
- Local course and organization of descending cortical fibers
- Crus-specific morphology, imaging observations and tissue integrity
- Localization of abnormalities and evidence supporting their functional interpretation
Out of scope
- Taxonomy, habitat and conservation of the organism containing the structure
- The entire cerebral peduncle or midbrain
- Substantia nigra nuclei and their intrinsic circuitry
- Complete corticospinal, corticonuclear and corticopontine pathways outside the crus
- Whole-patient diagnosis, prognosis and treatment planning
Why it exists Filled
Enable an agent to identify a cerebral crus, assess evidence about its descending fibers and tissue state, and determine which observations or specialist review are warranted.
Distinguishing features Filled
- The term identifies the anterior motor-tract-bearing portion of the cerebral peduncle. [NLM MeSH](https://www.ncbi.nlm.nih.gov/mesh/68065843)
- A candidate region must be checked against the substantia nigra boundary; a label encompassing adjacent gray matter requires clarification of the anatomical convention.
- It denotes a region containing multiple fiber populations, so a corticospinal tract label alone does not establish the full crus boundary.
- A cerebellar peduncle label does not establish cerebral crus identity; the parent structure and anatomical course must agree.
- The meaning of basis pedunculi must be checked in each source because anatomical conventions differ over inclusion of substantia nigra. [IFAA terminology notes](https://ifaa.unifr.ch/Public/EntryPage/TA98%20Tree/TA98%20EN/14%20TA98%20EN.htm)
What robots and AI may and may not do Filled
Must not
- Interpret a person's brain scan as a diagnosis.
- Predict recovery for a specific patient.
- Disclose a person's neurological records without consent.
- Present unproven therapies as able to repair damage.
Only with a human decision
- Treatment decisions after stroke or brain injury.
May
- Explain the anatomy of the cerebral crus in general terms.
- Advise a person with sudden weakness or eye movement problems to call emergency services.
Moral aspects Filled
- Brain injury affects identity and independence; families need honest information.
- Fast action in stroke saves function, so warning signs must not be downplayed.
Who is affected
- Stroke patients
- Families and carers
- Clinicians
Owners Filled
Steward
Nobody owns it; it is part of each person's body.
Links to other meta-models Filled
parent
- Q66590407 - registry parent class
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.cerebral-crus
- Wikidata: Q12738044 (https://www.wikidata.org/wiki/Q12738044)
Direct properties required Filled
- Laterality: left | right | bilateral aggregate | unspecified
- Species and developmental context: organism or specimen reference with species and age or developmental stage
- Anatomical boundary convention: named terminology or atlas, edition and explicit inclusion rules
- Measurement level: rostrocaudal landmark, section orientation and coordinate reference
- Cross-sectional area: mm² with segmentation method and measurement level
- Local fiber assignment: corticospinal | corticonuclear/corticobulbar | corticopontine | other supported assignment | unresolved
- Observed tissue condition: no abnormality detected | signal abnormality | volume loss | distortion | tissue disruption | indeterminate, with method and date
- Lesion overlap: mm³ or percentage of the defined crus region, with registration uncertainty
Recognition required Filled
- Two thick columns of white matter on the front of the midbrain, diverging upward toward the hemispheres.
Capabilities and actions required Filled
- Annotate a left or right cerebral crus in an image, section or specimen using explicit anatomical landmarks.
- Compare crus size and appearance across sides or time points with matched measurement methods.
- Link local fiber assignments to pathway models while retaining uncertainty about tract boundaries.
- Quantify overlap between an abnormality and the crus separately from neighboring midbrain structures.
- Request better imaging, anatomical adjudication or specialist interpretation when the evidence cannot resolve the crus boundary or condition.
Hazards and failure modes required Filled
- Strokes here can cause weakness on the opposite side of the body.
- Brain swelling can push tissue against it and cause paralysis.
Standards and interfaces required Filled
- Terminologia Anatomica, issued by the Federative International Programme for Anatomical Terminology, standardizes the anatomical name crus cerebri.
Context of use required Filled
- The cerebral crus is studied in midbrain anatomy, neuroimaging and examination of nervous tissue.
- Its descending motor pathways help specialists relate the location of tissue damage to disturbances of movement.
Sources Filled
- Wikidata item Q12738044: cerebral crus - identity and sense of the item
- Wikipedia: Cerebral crus - general description of the item
Open questions
- Which anatomical terminology and atlas should govern the registry boundary when sources use cerebral peduncle or basis pedunculi differently?
- Does the registry intend a human reference concept or a comparative anatomical concept spanning specified species?
- How reliably can the principal descending fiber populations be localized within the crus at different rostrocaudal levels using available primary anatomical evidence?
- Which measurement protocols and reference populations support interpretation of crus asymmetry or volume change across development and aging?
- What primary evidence resolves local vascular supply and distinguishes direct crus injury from secondary degeneration in a particular observation?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q12738044/spec.json